An internal combustion engine with a mass equalization gear mechanism according to the class is known from U.S. Pat. No. 2,914,963. The mass equalization gear mechanism that is arranged underneath the crankshaft as a so-called Lancaster balancing device with two balancing shafts rotating in opposite directions at twice the rotational speed of the crankshaft simultaneously comprises the pump of the lubricating oil circuit of the internal combustion engine, in that the intermeshing drive gearwheels of the balancing shafts form a gear type pump. Their task also consists in keeping the gearbox housing oil-free in the area of the chain drive of the balancing shafts, in order to counteract oil foaming due to the rotating chain wheel. The end sections of the balancing shafts are supported in the gearbox housing by means of rolling bearings connected to the lubricating oil circuit.